import re
with open(r'c:\tools\disp_arp.txt') as data:
	for line in data:
		print(line.strip())

line = '172.29.50.150   4c1f-ccb4-5157            I -  Vlanif41'
match=re.search(r'(?P<ip>\d+\.\d+\.\d+\.\d+) +(?P<mac>\w+-\w+-\w+) +.* (?P<port>\S+)',line)
print(match.groups())
print(match.groupdict())